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Finding the Fourth Proportional to 639, 881.94 and 418.20

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Solution

The fourth proportional to 639, 881.94 and 418.20 is: 577.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    639 : 881.94 = 418.20 : x
  2. Step 2: Convert to fraction form
    639/881.94 = 418.20/x
  3. Step 3: Cross multiply
    639x = 881.94 × 418.20
  4. Step 4: Simplify right side
    639x = 368,827.31
  5. Step 5: Solve for x
    x = 368,827.31/639
  6. Step 6: Final answer
    x = 577.19

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.